Question: Simplify the following expression: $t = \dfrac{6}{3z} - \dfrac{-6}{3z}$
Solution: Since the expressions have the same denominator we simply combine the numerators: $t = \dfrac{6 - (-6)}{3z}$ Combine like terms: $t = \dfrac{12}{3z}$ Simplify by dividing numerator and denominator by 3: $t = \dfrac{4}{z}$